Lamp socket



June 2 1942 o. H, sPARLlNG 2,285,175

LAMP SOCKET Filed July 24, 1940 INVENTOR ATTORNEY Patented June2, l 2-v Flcl:

l n LAMP SOCKET. y

` Oliver H. Sparling, Seattle, Wash., assigner of one-third to W. Paul Heath and one-third to Bertram T. Heinz, both or sesttlefwash.

Application July 24,

y I 3 Claims. My invention relates to lamp sockets and more `particularly to a socket lfor electric lamps of the double-ended discharge type.

. At the present time iiuorescent` tubes or discharge type lamps are being increasingly used as a source of illumination. 11n such discharge tubes filament-electrodes are positioned at the respective' ends of the tube and electrical energy is dissipated between the electrodes by way of the gaseous medium within the tube. As` the iliament at each end of the tube is illuminated, there willl be suiiicient glow within the gaseous medium to facilitate the discharge through` the gaseous medium and the said filaments therefore function as a starting` device. By various means well known in theart, after discharge through the gaseous medium is started, the illumination of the filaments at the respective ends of the 'tube is automatically stopped.

The construction of discharge tubes as now 4commonly made, thuscomprlses filaments and 4electrodes positioned at the` respective ends of the-discharge tube and two contact'prongs at the respective ends oi the discharge tube, per- -mitting the discharge of energy from one elec.-

trode at one end to a second electrode at the other end by way of the gaseous conductor. It is necessary that two contact prongs or pins be e provided at each end `of the discharge tube.

A number of sockets are available on the mar- V ket for mounting such discharge lamps and which are provided with prong or pin receiving clips. However, such sockets havemany shortcomings. One of` the dimculties encountered in the art is the limitations of the types of ilxtures which maybe constructed employing` present day sockets. Generally speaking, present day sockets are provided with a slot or slots and, to operatively connect a tube with a socket, the tube is moved transversely so that the two pins or prongs on each end of the discharge tube are inserted into a slot. In one type. now on the market, thereafter the tube is angularlyinoved approximately ninety degrees and thetube thus secured in position.

To provide suillcientroom for the pins. or prongs in the socket, very substantial depth is required of the socket, which depth in itself provides a serious shortcoming in the appearance of the completed fixture! Also as `the pins or prongs of the tube are moved transversely into position, the socket must be adjacent an edge of the iixture so as to provide an unobstructed slot for reception of the pins or prongs oi the tube. Still other problemsV which exist in the art by 1940, serial No. 341,252

(c1. 17a-sas) reason of present day sockets, residein the necessary open construction leaving exposed contact inthe sockets and serving as a gathering place for dirt, dust, insects and thel like. It is an object of the present invention to `provide a socket which will overcome the various shortcomings in the art-above mentioned, and to provide a socket which is completely enclosed and'characterized by the absence of exposed contacts. It is a further object to provide asocket so that' the contacts are protected against the various elements of dust, insects, etc., and which eliminates contact troubles resulting from air-borne materials or insects. Whenever the contacts are exposed tov material which may `be borne in heran-as dust, grease, insects, salt and many o ,oorrosion of the pins and receiving clips will result providing non-conductor materials thereon and inoperativeperiods will result. These various 20 difficulties are well known in the'art and are generally termed contact troubles.

It is another object of the invention to provide a socket whichwill receive a tube by longitudinal movement thereof so that the socketmay be of any desired shape. One desired shape ofthe socket is a circular shape as the framework of a fixtures may be readily punched to provide the same. It is another'object of the invention to provide a socket which is so designed as to provide for a minimum depth, thus permitting streamlining of fixtures and the minimizing oi non-illuminated portions. It is a-further object of the invention to provides socket construction whereby visible indication'may be had that the tube lamp is locked securely in place. In present day sockets the only manner of determining whether the tube lamp has been properly positioned and is locked in place is by twisting or turning the tube lamp, and because of the ab- 40 sence of any visible means indicatingv whether a lamp has been properly secured in place many lamps have been dropped and broken andthe losses by reason of this shortcoming` is a substantial one.

`It is another object of the invention to provide a socket which will insure positive and rm contact between the receiving clips in the socket and vthe pins or prongs of the tube lamp.

kIt is another object of the invention to provide a socket which will eliminate any necessity for twisting or turning the tube lamp. In present day sockets, inthe event of displacement of members in the socket, damage to lamps and sockets hasresulted because of twisting the plus 5; against relatively iixed'members. Also the plusv or prongs at the end of the lamp become somewhat loosened in the normal twisting required. It is an object of my invention to provide a socket where the pins are inserted longitudinally into the socket and all twisting of the lamp is eliminated.

Another type of socket commonly used on the market is provided'with spring clips so that the lamp islinserted in a transverse direction. In case the spring clip., are misaligned, pressure in this transverse direction will tend to loosen the pins or prongs of the lamp and further damage the socket. l c

The above mentioned general objects of my invention, together with others inherent in the same are attained by thel mechanisms illustrated in the following drawing, the same being preferred exemplary forms of embodiment of my invention, throughout which vdrawing like reference numerals indicate like parts:

Figure 1 is a side'elevation of a tube lamp xture provided with sockets constructed in accordance with this invention, the outlines of a tube lamp and the sockets therefor being shown by dotted lines;

Fig. 2 is a bottom plan View of the apparatus shown in Figure 1;

Fig. 3 is a sectional view taken substantially cn broken line 3-3 of Figure 1;

Fig. 4 is adetached elevation, with parts broken away, of a tube lamp used in connection with this invention; l

Fig.'5 is a fragmentary sectional view, on a larger scale than Fig. 2, taken substantially on broken line 5-5 of Fig. 2, and showing one of my lamp sockets in side elevation;

Fig. 6 isan elevation, with parts broken away, and looking in the direction ofV broken'line 6-6 of Fig. 5, parts being shown by dotted lines;

V Fig. 7 is a detached rear elevation of my socket indicated by broken linesy looking in the direction 1--1 of Fig. 5;

Fig. 8 is a. sectional view taken substantially on brokenline 8-3 of Fig. '6 and showing parts in elevation;

iFig. 9 is a sectional view in elevation;

Fig. 10 is a plan view looking into the socket with the face plate thereof removed;

Fig. 11 is a detached perspective view of the Fig. 13 is a fragmentary view, partly in section and partly in elevation, illustrating the operationof resilient electrical contact clip means used in my lamp socket, and showing by dot "1d dash lines, positions that parts may assume w en a lamp is being inserted in this lamp socket;

Fig. 14 is a view partly in elevation and partly in section showing mounting means for my sock et that differs from the mounting means shown in the preceding gures; and

Fig. 15 is an elevation, with parts broken away, illustrating a tube lampl in the mounting means shown in Fig. 14 and a bracket means which may bev used for supporting the rame.

As illustrative of one mounting for my socket,

Figs. 1, 2, 3, 5 and 6 show one type of lamp iix-i ture means with which said socket may be used. These figures show a rectangular lamp housing comprising a at top plate 20 hung from overhead taken substantiauy v on broken line 9-9 of Fig. 5, parts being shown top plate 20 and extend downwardly therefrom, as best shown in Fig. 5, and circular openings 23 are provided in the end plates 22 for the reception of the cylindrical housing portions 24 of my socket. Preferably outer end plates 25 are positioned in outwardly spaced relation from the end plates 22 to provide chambers 26 for the socket member housings 24. 'Ihe outer end plates 25 are preferably removably connected with the fixture housings by screws 21 to provide easy access to the chambers 26. y

An auxiliary housing portion 28 of inverted trough shape is secured to the main fixture hous- `ing to provide an ornamental design and to provide a housing for the usual auxiliary or starting apparatus employed in tube lighting.

The 'circular socket receiving openings 23 in the end plates 22 are preferably provided with notches 29 at one or more points to receive lugs 29 on the socket housing 24 and compel the correct positioning of the socket housings 24. In the drawing, see Figs. 5, 6 and 9, I lhave shown notches 29 and lugs 23' provided at .two diametrically opposite locations but the position and number of these lugs obviously may be varied.

Fig. 3 shows reflectors 30, light reiiective side walls 3|, and light reflective partitions 32 all vextending longitudinally and cooperating with a plurality of longitudinally extending tube lamps 33 to reect light in a desired direction. Obviously any desired reflectors, housing members and the like may be used in place of those shown I in the drawing.

The lamp socket shown in Figs. 5 to 15 comprisesgthe cup shaped cylindrical housing 24 that is adapted to t into one of the cylindrical openings y23 in the end plates 22 and is provided adjacent one end with external flange means 36 adapted to rest against the end plate 22 and form a stop. Obviously the external shape of the housing 24 and flange 3S may be varied.

The housing 24 is provided with a bottom portion 31 that has two internal trough shaped parallel grooves 38 extending crosswise thereof on opposite sides of the center for the reception of two spring contact clip members each formed of nat resilient metal.

Each spring contact clip member comprises a fiat base portion 40 having an uptumed perforated portion 4|- at one end and a reversely bent or U shaped portion 42 at the other end. The U shaped portion 42 is connected with an outer spring portion 43 that terminates in an outwardly bent contact member 44. The contact member 44 has a concave groove 45 extending longitudinally thereof and a depression 46 is preferably formed in the spring portion 43 at the base of the groove 45. The groove 45 and depression 46 are adapted to receive and make electrical contact with the side portionand end portion respectively of one of the pins or prongs 35 on the end of a tube lamp 33 as best shown in Fig. 13.

When the spring contact clip -members are properly positioned and secured in the housing 24, the base 'portion of each contact member extends under an integral bridge portion 41 of the housing and the perforated lug 4| of the spring contact member is secured to the bridge portion 41 by a tubular rivet member 48, Figs. 8 and 13. The interior of each tubular rivet 48 is threaded for the reception of a screw 49 by which suitable circuit wires 50, Fig. v8, are connected with the spring contact clip members.

supports 2|. End plates 22 are secured to the 75 An end plate or disc 5| of a suitable size to lit telescopically within the socket housing 24 is provided `at two diametrically opposite locationswith Iwo marginally positioned1 perpendicular side flanges 52 that extend into` the socket housingV 24 and serve as guide means for the end plateil. Ihe side flanges 52 have slots 53 therein for the reception of pins 54 that extend through the sides of the socket housing 24 and through the slots 53, as shown in Fig. 9. The pins 54 limit the outward movement of the end plate 5| to a position substantially flush with the front of the housing 24. y

To arcuate holes 55 in the bottom portion 31 of the housing 24provide clearancefor movement of the side flanges 52 when the end plate 5l is pushed into said housing 24 into a positionA as shown by dot anddash lines in Fig. 13. This.

occurs when artube lamp 33 is being inserted. ,f' Two holes 56 are provided in the end plate 5IA for the reception of the two pins 35 on the lend portion of a tube lamp 33.

The socket housing 24 is externally provided with an annular groove 56 for the reception of a spring vclip 51 (Fig. 6) that snaps into said groove 56 and has two end portions 53 that engage with 'lamp is in its normal operating position. In this position ofthe lamp both pins at both ends of the lamp will be in side and end contact with their respective contact slip springs substantially as shown by full lines in Fig. 13.

Obviously the end plate of onesocket of each pair can be fixed and non-movable and the lamp can be inserted by pressing one end portion of a lamp tube into the socket having the movable end plate a distance at least equal to the length of the pins 35 at one end and then letting the lamp tube move back toward the socket with the non-movable end plate after the pins 35 on that end are properly alignedwith the holes. thus seen that at least one of the sockets of each pair is to be provided with resilient means to allow an end portion of the lamp tube to be ina position substantially as shown by dot and dash the Lend plate 22 to hold the socket housing in assembled relation with the plate 22.

To facilitate connection of my socket members with various types of brackets adapted to be used independently of fixtures of the type shown in Figs. 1, 2, 3 and 5, I provide in the socket housing 24 adjacent the flange 36, a groove 60 (Fig, 13) within which an inwardly deformed end portion 6l of a cup shaped metal shell 62,---

The shell 62 Figs. 14 and 15, may engage. has a split 63 in the side thereof to provide for enough expansion so that the socket housing 24 may be inserted therein and removed therefrom. The shell 62 has a tubular boss 64 on the outer end thereof and preferably an internally threaded bushing 65 is xedly secured within the boss 64 to receive externally threaded end portions of combined support and circuit wire conduit members 66. The members66 may be attached to any xed support, such as a ceiling or a wall or a In the use of this device two of these sockets are supported in alignment with each other and spaced apart just far enough to allow a tube lamp of a predetermined standard length, measured from end to end exclusive of the pins or i prongs 35, to be positioned therebetween. To engage the tube lamp 33 with the sockets the pins 35 on one 'end of the tube lamp are first inserted in the holes 59 in the resiliently supported end plate 5| of one socket and said end plate 5| is pushed inwardly to substantially the position shown by dot and dash lines in Fig. 13. This allows the pins 35 on the other end of the tube lamp 33 to just clearthe face of the other socket and they are properly positioned to enter the holes 59 in the end plate 5| of said other socket. The pins 35 may be urged into the holes 59 in the end plate 5| of said other socket or the tube lamp may be released. When the tube lamp .is thus released the reaction of the deflected spring clips in the socket 24 at the iirst inserted end of the tube lamp will move said tube lamp toward the other socket until the two ends of the tube lamp are substantially ush with the face portions oi the respective sockets and the tube serted thereinto in applying the tube to or removing it from the receptacles.A

When the contact springs or clips are pressed inwardly in inserting a lamp 33, they will assume lines in Fig, 13 and will only lengage with the end portions of the pins 35. When the tube lamp 33 moves to its correct operating position the contact springs or clips will move outwardly into the full line position shown in Fig. 13 and will make electrical contact with both the side portions and the end portions of the pins 35. Also when the contact springs are in full engagement with the pins 35, the tip portions of said contact springs will engage with the end plates 5I and prevent lost motion or play of said end plates.

As the pins 35 are moved into engagement with or are withdrawn from engagem'ent with the contact springs, said pins 35 will have a wiping action on the portions 45 of the contact springs or clips and this will tend to keep the contacting parts clear of corrosion and insure good electrical contact.

The end plate 5I substantially closes the sock-...

et housing 24 in which the contact springs or clips are disposed and helps to exclude dust, moisture, insects and the like, thereby minimizing the danger oi' contact trouble due to corrosionand foreignrmaterial. The spring contact members always tend to maintain good electrical contact with the pins 35. 'I'his is of great advantage in a tube lamp of this type which operates on low amperage. as it helps to minimize contact troubles.

The socket member of my invention is of shallow depth and is compact and takes up little space, thus minimizing the restrictions imposed by said sockets in the design of lighting fixtures, especially as respects streamlining of the fixture and the housing portions.

The tube lamp is inserted in the socket by endwise movement rather than by sidewise or sidewise and twisting movement. This avoids danger of injury to the lamp and socket inherent from sidewise `or twisting movement and also provides visible indication as to whether or not the lamp is properly inserted, thus avoiding the danger of leaving the lamp in such a condition lIt istacle' having a substantially closed end portion; an end plate telescopically movable within said receptacle in spaced relation to said substantially closed end portion, said end plate having holes therein through which tube lamp contact pins may extend into said receptacle; slotted guide members rigid with said end plate and cooperating with said receptacle to guide said end plate, the closed end portion of said receptacle having slots within which said guide members operate; stop means operable in the slots of said guide members to limit the outward movement of said end plate; and contact springs within said receptacle yieldingly supporting said end plate and positioned for electric contact with contact pins that extend through said holes in said end plate.

2. In a lamp socket for tube lamps having projecting contact pins at each end, a tubular receptacle having a substantially closed end portion; an end plate telescopically movable within said tubular receptacle in spaced relation from said closed end portion, said movable en d plate having two spaced apart holes therein to provide for the passage therethrough of two tube light' contact pins; means limiting the outward movement of said movable end plate; and two substantially U shaped contact springs of nat resilient metal secured within the receptacle, each contact spring having a contact portion extending toward said movable end plate and normally engaging and resiliently supporting said movable end plate and positioned to make both end contact and side contact with tube lamp contact pins that are inserted throughl the two holes in said movable end plate.

3. In a lamp socket for tube lamps having projecting contact pins at each end, a tubular receptacle having a substantially closed end por` tion; an end plate telescopically movable within said tubular receptacle in spaced relation from said closed end portion, said movable end plate having two spaced apart holes therein to provide for the passage therethrough of two tube light contact pins; stop means limiting the Outward movement of said movable end plate; and tw flat resilient contact springs secured within said receptacle resiliently supporting and urging said end plate normally against its said stop means and depressible with said plate means a minimum distance equal to the length of the tube light projecting contact pins, said contact springs being further mounted in alignment with the holes in the said end plate for electrical engagement with the projecting pins of a tube lamp.

OLIVER H. SPARLING. 

